Flap folding apparatus for envelope making machines

ABSTRACT

Machine for producing envelopes has a flap folding apparatus whereby the flap of an envelope is optionally folded against its rear side, or after being previously folded is opened once again, or is folded against the front side of the envelope. The apparatus has a first suction cylinder and delivery discs. The invention is particularly characterized in that between the first suction cylinder and the delivery discs there are provided a second and third suction cylinder preceded by an adjustable stop abutment and a flap opener and associated with a folding pocket and a folding cylinder. The apparatus has three operational possibilities. According to the first one, each envelope with a closed flap is conveyed by the suction cylinders into a slot of the delivery discs. According to the second operation each envelope is conveyed by the first suction cylinder to a stop abutment, then is gripped by the third suction cylinder and is conveyed in the opposite direction to a flap opener, so that the envelope with an open flap is conveyed into the slot of the delivery discs. According to the third operation each envelope which is provided with a precreased folding edge and a flap is transferred by the first and second suction cylinders into a folding pocket and then is conveyed by the third suction cylinder under a folding cylinder and into a slot of the delivery discs.

United States Patent Ehlscheid 1 1 Feb. 22,1972

[54] FLAP FOLDING APPARATUS FOR ENVELOPE MAKING MACHINES Guenter Ehlscheid, Neiderbieder, Germany [72] Inventor:

Winkler 8: Duenne bier, Neuwied am Rhine, Germany [221 Filed: Sept. 23, 1970 21 Appl.No.: 74,661

[73] Assignee:

Primary Examiner-Bemard Stickney Attorney--Richards & Geier [57] ABSTRACT Machine for producing envelopes has a flap folding apparatus whereby the flap of an envelope is optionally folded against its rear side, or after being previously folded is opened once again, or is folded against the front side of the envelope. The apparatus has a first suction cylinder and delivery discs. The invention is particularly characterized in that between the first suction cylinder and the delivery discs there are provided a second and third suction cylinder preceded by an adjustable stop abutment and a flap opener and associated with a folding pocket and a folding cylinder. The apparatus has three operational possibilities. According to the first one, each envelope with a closed flap is conveyed by the suction cylinders into a slot of the delivery discs. According to the second operation each envelope is conveyed by the first suction cylinder to a stop abutment, then is gripped by the third suction cylinder and is conveyed in the opposite direction to a flap opener, so that the envelope with an open flap is conveyed into the slot of the delivery discs. According to the third operation each envelope which is provided with a precreased folding edge and a flap is transferred by the first and second suction cylinders into a folding pocket and then is conveyed by the third suction cylinder under a folding cylinder and into a slot of the delivery discs.

3 Claims, 5 Drawing Figures PAIENTEIJFEB22 I972 SHEET 2 BF 3 Inventor G. 5 15c hedc'l BS dhww'da 5-52.81!

ATTo mm 15 PATENIEnrzazz 1912 3. 643 555 SHEET 3 OF 3 Inventor G, 56/5 c/ze L'c/ C53 maum j ATTORN E55 FLAP FOLDING APPARATUS FOR ENVELOPE MAKING MACHINES This invention relates to a flap folding apparatus for use in envelopemaking machines. The term envelope" as used hereinafter is intended to include flat bags and other similar articles. The invention is particularly concerned with an apparatus of this type wherein the envelopes can be delivered from the machine optionally with the flap folded against the rear of the envelope, or with the flap reopened after preceding folding or with the flap folded against the front of the envelope.

ln known machines for producing such envelopes, the envelopes delivered from the machine are usually collected on the machine delivery table with the envelope flap folded against the rear of the envelope. In some machines it is also possible for the finished envelopes to be delivered with the flap in the open state in that the flap, precreased along its subsequent folding line, is not folded, so that the envelopes are collected on the delivery table of the machine with the flap merely precreased but being open.

Widely used machines for the automatic filling of envelopes usually operate with envelopes having an open flap. However, if the flap was only precreased during the manufacture of the envelopes, and was not therefore first folded and then reopened, the folding when the flap is closed after the envelopes are filled cannot proceed with reliability and accurately on the only slightly weakened crease.

ln envelopes for tote betting slips it is to some extent common practice to insert a betting slip into an envelope whose flap is folded against the front thereof, so that the betting slip is visible. Folding of the flap against the front of the envelope is however not generally possible with known machines for the production of such envelopes.

An object of the present invention is to improve existing flap folding apparatus and to make it adapted to various operations.

Another object is the provision of a flap folding apparatus which will make it possible to deliver envelopes with their flaps being optionally folded against the rear thereof, or being reopened after previous folding, or being folded against the front of the envelope.

Other objects of the present invention will become apparent in the course of the following specification.

In the accomplishment of the objectives of the present invention it was found desirable to provide an apparatus wherein a second and third suction cylinders are provided between a first suction cylinder and a delivery disc adapted to individually receive envelopes from the last suction cylinder, the second and third suction cylinders being preceded by an adjustable stop abutment and a flap opener and being associated with a folding pocket and a folding cylinder, known means being provided for controlling the suction air which retains the envelopes on the suction cylinders.

The apparatus can be operated optionally in the following three ways:

a. each envelope with a flap which remains closed is conveyed by the first suction cylinder of the apparatus to the second and third suction cylinders and thence into a slot of the delivery discs, or

b. each envelope, with its flap closed and leading in the conveying direction, is entrained by the first suction cylinder of the apparatus and conveyed to a stop abutment, is then gripped on its other end by the third suction cylinder in order to be conveyed, in the direction opposite to the previous direction and past a flap opener for opening the flap and, with the flap thus opened, is conveyed into a slot of the delivery discs, or

c. each envelope, obtained from the last suction cylinder of 7 the folding machine and having a precreased folding edge and a flap which trails in the conveying direction, is transferred by the first suction cylinder of the apparatus via the second suction cylinder into the folding pocket while the third suction cylinder draws up the envelope at a position closely upstream of the crease of its open flap to convey the envelope, with its flap folded against the front thereof, below the downstreamdisposed folding cylinder into a slot of the delivery disc.

If the folding machine is adapted to deliver only envelopes with a closed flap which leads in the conveying direction, it is possible for the flaps of the envelopes to be folded by the apparatus according to the present invention against the front of the envelope so that each envelope obtained from the las suction cylinder of the folding machine is entrained by the first suction cylinder of the apparatus as far as a stop is then gripped at its other end by the third suction cylinder of the apparatus in order to be conveyed in the direction opposite to the previous direction and past a flap opener for opening the flap and is thus conveyed by the second suction cylinder into the downstream-disposed folding pocket, while the third suction cylinder draws up the envelope at a position closely upstream of the crease of the open flap to convey the envelope below the downstream-disposed folding cylinder into a slot of the delivery discs.

According to the present invention, the first suction cylinder of the apparatus comprises a middle part adapted to rotate in the conveying direction of the incoming envelopes and two side parts, adapted to rotate at the same speed and concentrically to the middle part but in the opposite direction. The third suction cylinder of the apparatus is provided with friction members which, when the conveying direction is changed, thrust the envelopes obtained in accordance with the second operational possibility from the third suction cylinder, against the two side parts of the first suction cylinder to prevent displacement of the envelope relative to its desired position, such displacement being otherwise unavoidable if the stationary envelope is accelerated only by rotating suction apertures.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings showing by way of example only, a preferred embodiment of the inventive idea.

In the drawings:

FIG. I is a longitudinal section through the delivery end of the machine with the apparatus adjusted for envelopes having the flap folded against their rear side;

FIG. 2 is a longitudinal section according to FIG. 1 but set up for envelopes with an open flap;

FIG. 3 is a longitudinal section corresponding to FIG. I but set up for envelopes with the flap folded against their front;

FIG. 4 is a longitudinal section through the first and third suction cylinders of the apparatus along the line lVlV of FIG. 1;

FIG. 5 is a cross section through the first and third suction cylinders of the apparatus along the line VV of FIG. 4.

Referring to FIGS. I'to 3, the parts of the known folding machine comprise the feed cylinders 5 with mating cylinders 6, a suction cylinder 7 with mating cylinder 8, a folding pocket 9 and a folding cylinder 10.

The principal parts of the apparatus according to the present invention comprise a first suction cylinder 11, a second suction cylinder 12 and a third suction cylinder 13, an adjustable stop abutment 14, associated with the first suction cylinder, a flap opener 15, a folding pocket 16, associated with the second suction cylinder and a folding cylinder 17 associated with the third suction cylinder. The flap opener 15 may be provided with a row of small apertures 46 from which air is blown against the flap to be opened. The apparatus according to the present invention is followed by delivery discs 18 with a plurality of arcuate slots 19 and by a delivery table 20 having strippers 20.

The cylinders S, 6, 7, 8, 10, 11, 12, I3 and 17 as well as the delivery discs 18 are supported in folding machine walls (not shown in FIGS. I to 3) and are adapted to rotate in the direction of the rotational arrows shown in the drawings. The suction cylinders 7, ll, 12 and 13 have the same circumferential speed and are each adapted to deliver one envelope for each revolution. In the interests of clarity, the distance indicated in FIGS. 1 to 3 between the individual envelopes traversing the cylinders was reduced to approximately half the actual distance. For each incoming envelope, the delivery discs 18 rotate by an amount equal to the pitch between two slots 19. The first suction cylinder 11 of the apparatus comprises a middle part 22, fixed on to a shaft 21, and adapted to rotate in the direction of the arrow M, and two side parts 23, rotatably mounted on the shaft 21 and operating at the same speed in the direction of the arrow S (see also FIG. 4).

Guides 34 for the envelopes 1, completely folded with the exception of their flap, are provided between the cylinders 5 and 7, the bottom edge 2 of each envelope leading in the conveying direction, while the closing flap 4, precreased along the subsequent folding line 3, trails in the conveying direction. Depending on the size of the envelopes, the folding pocket 9 is provided with stops 25, adapted to be adjusted after releasing the screws 24, and having guides 26. The suction cylinder 7 is provided with a row of suction apertures 27 to which timed suction is supplied in known manner through a bore 28 and an arcuate control slot 29 so that these apertures draw up each envelope arriving below the mating cylinder 8 at a position closely upstream of the crease 3 of its flap 4 and, after the leading edge 2 of the envelope strikes the stop 25 of the folding pocket 9, the envelope is entrained by the suction apertures while the envelope flap is folded under the folding cylinder 10 and is then transferred to the first suction cylinder 11 of the apparatus according to the present invention.

The middle part 22 of the first suction cylinder 11 is provided with a row of suction apertures 31 which are supplied with timed suction through an arcuate control slot 33 of a known control slide 35 so as to entrain the envelopes. The envelopes are drawn up at a position closely behind their crease 3 and taken over from the suction cylinder 7 and, depending on the adjustment of the control slide 35 the envelopes are either transferred to the second suction cylinder 12 or the envelopes are entrained under guides 36 to stop abutments 14, adjusted in accordance with the size of the envelopes, for transfer to the third suction cylinder 13 which the envelopes by means of a row of suction holes 40 at a position immediately upstream of its bottom edge 2 and entrains such envelopes in a direction opposite to their previous conveying direction. In the interests of clarity, the path taken by the suction air for the first suction cylinder 11 is shown in FIGS. 1 to 3 in a manner different from the actual embodiment illustrated in FIGS. 4 and 5.

The second suction cylinder 12 is provided with a row of suction apertures 37 which are supplies with timed suction through a bore 38 and an arcuate control slot 39 so that an envelope, obtained from the first suction cylinder 11, is either transferred to the third suction cylinder 13 or is supplied to the folding pocket 16.

The third suction cylinder 13 is provided with a row of suction apertures 40 and further suction aperture rows 40', 40", 40", disposed upstream thereof in the direction of rotation and being supplied with timed suction through apertures 41, 41, 41" and 41" and an arcuate control slot 42, so that they either transfer an envelope obtained from the first suction cylinder 11, or from the second suction cylinder 12 into a slot 19 of the delivery discs 18, the suction aperture rows 40 to 40" becoming inoperative in the sequence 40, 40, 40", and 40' when an envelope is inserted into a slot 19, so that the last row of suction apertures still supplies thrust while the downstream disposed suction aperture rows have already released the envelope. The delivery discs 18 transfer the envelopes in succession and in upright form onto the delivery table 20 with the strippers 20', on which table they are collected in known manner upstream of a movable fence 45.

The folding pocket 16 associated with the second suction cylinder 12, is provided with stop abutments 44 which can be adjusted to the size of the envelope after releasing the screw 43. If the envelopes are to be delivered with their flap folded against the envelope front, the suction cylinder 12 will deliver the envelopes to the stops 44, the envelopes being drawn up at a position closely upstream of their front edge which leads in the conveying direction. The third suction cylinder 13 will then draw up the envelope bearing upon the suction cylinder 12 to a position closely upstream of the folding edge 3 of its flap 4 by means of the row of suction apertures 40, guide the envelope below the folding cylinder 17 while folding the flap against the envelope front and push the envelope into a slot 19 of the delivery discs 18 which place the envelopes successively and in upright form onto the delivery table.

FIGS. 4 and 5 show details of the first suction cylinder 11 and of the third suction cylinder 13 of the apparatus. Both cylinders are rotatably supported in side walls 47. The first suction cylinder 11 comprises the middle part 22, fixed upon the shaft 21 and the two side parts 23, disposed adjacently on both sides of the middle part and adapted to rotate loosely on the shaft 21. The side parts 23 have the same external diameter as the middle part 22, their externally disposed ends being constructed as spur gears 48. Suction air is controlled by the control slide 35 which communicates via a longitudinal bore 32 with the suction apertures 31 of the middle part 22. The shaft 21 and the middle part 22 fixed thereon are driven by a spur gear 49.

The third suction cylinder 13 comprises a cylinder member 30, fixed upon a shaft 50 and provided on its surface with resilient friction members 51, a known control slide 52, not described in detail, for controlling the suction air for the suction aperture rows 40, 40, 40", 40" via the suction apertures 41, 41', 41", 41" and spur gears 53 disposed adjacently on both sides of the cylinder member 30 and fixed upon the shaft 50. The third suction cylinder 13 is driven by a spur gear 49. The resilient friction members 51, firmly connected to the cylinder member 30, project slightly from the cylinder surface and, during rotation of the cylinders, are in temporary and direct contact with the side parts 23 of the first suction cylinder 11. The cylinder member 30 of the third suction cylinder 13 and the middle part 22 of the firstsuction cylinder 11 do not touch each other but are separated by a distance corresponding to the thickness of a folded envelope.

The spur gears 49 and 49' on the first suction cylinder 11 and on the third suction cylinderl3' respectively, are driven in common by a broad spur gear disposed on the shaft of the second suction cylinder 12 but not shown. The spur gears 48 of the side parts 23 of the first suction cylinder 11 mesh with spur gears 53 which are fixed upon the shaft 50 of the third suction cylinder 13. The middle part 22 of the first suction cylinder 11 and the third suction cylinder 13 rotate in the same direction since they are driven in common by the spur gear of the second suction cylinder 12, while the side parts 23 of the first suction cylinder 11 rotate in the direction opposite to that of the third suction cylinder 13, namely, the side parts 23 roll upon the projecting resilient friction members 51 of the third suction cylinder 13.

The effective lengths of the arcuate control slots 33 of the first suction cylinder 11, of the arcuate control slots 39 of the second suction cylinder 12 and of the arcuate control slots 42 of the third suction cylinder 13 are variable. The lengths of the appropriate suction distances will depend on whether it is intended to deliver, as illustrated in FIG. 1, envelopes with flaps folded against the rear thereof, or, as illustrated in FIG. 2, envelopes with open flaps, or, as illustrated in FIG. 3, envelopes with flaps folded against their front. The control slots 29, 33, 39 and 42 are followed by fresh air slots, not shown, which permit the filling of the vacuum in the suction aperture rows of the cylinders prior to transfer of the envelopes to the succeeding suction cylinder.

Referring to FIG. 1, the last suction cylinder 7 of the folding machine has a control slot 29 of constant length. The first suction cylinder 11 of the apparatus of the present invention takes over the envelopes having their flaps folded against the rear of the envelopes, when the suction aperture 28 of the cylinder 7 has reached the end of the control slot 29 and at the same time suction is applied to the suction aperture 32 of the middle part 22 of the first suction cylinder 11 at the beginning of the control slot 33. The envelopes are entrained on the first suction cylinder 11 until the suction aperture 32 leaves the control slot 33 and transfers the envelopes to the second suction cylinder 12 whose suction port 38 is positioned at the beginning of the control slot 39. The envelopes are then entrained until the suction port 38 ceases to receive suction at the end of the control slot 39 and the suction port 41 of the third suction cylinder 13 simultaneously takes over the envelopes at the beginning of the control slot 42, the envelopes being subsequently conveyed into the slots 19 of the delivery discs 18 in the manner already described.

Referring now to FIG. 2 which illustrates the delivery of envelopes having flaps which are reopened after previous folding, the control slot 33 of the first suction cylinder 11 is so adjusted that the envelopes are entrained as far as the stop 14 on the middle part 22 adapted to rotate in the direction M of the arrow and are subsequently thrust by the friction members 51 of the third cylinder 13 illustrated in FIGS. 4 and 5 against the side parts of the first suction cylinder 11, rotating in the direction S of the arrow and are entrained by the third suction cylinder 13 under the flap opener 15 and in the direction opposite to their previous conveying direction, into the slots 19 of the delivery discs 18. The beginning of the suction slot 42 of the third suction cylinder 13 is so adjusted that the envelopes are directly taken over by the third suction cylinder 13 from the first suction cylinder 11. The second suction cylinder 12 does not participate in the passage of envelopes whose flaps are reopened after preceding folding.

Referring now to FIG. 3 which illustrates the delivery of envelopes whose flaps are folded against the front thereof, these envelopes, creased along the subsequent folding edge 3 and finish folded with the exception of the flap 4, are transferred by the last suction cylinder 7 of the folding machine to the first suction cylinder 11 of the apparatus of the present invention. From there and with their bottom edges 2 leading, the envelopes are transferred to the second suction cylinder 12 whose control slot 39 is so adjusted that the envelopes are entrained so that their bottom edge 2 strikes the stop 44 of the folding pocket 16. The suction aperture row 40 of the third suction cylinder 13 will in meantime have gripped the envelope at a position closely upstream of its creased folding edge 3 to guide it, with the flap folded against the front, under the folding cylinder 17 into the slots 19 of the delivery discs 18.

l Claim:

1. A flap folding apparatus for an envelopemaking machine, said apparatus comprising a first suction cylinder receiving the made envelopes, a second suction cylinder, a third suction cylinder, said second and third suction cylinders being located adjacent said first suction cylinder and being adapted to receive envelopes from said first suction cylinder, an adjustable stop abutment adjacent said first suction cylinder, a flap opener adjacent said first and third suction cylinders, a folding pocket adjacent said second and third suction cylinders, delivery discs adjacent said third suction cylinder, and means actuating said suction cylinders for transmitting an envelope the flap of which remains closed consecutively by first, second and third suction cylinders to the delivery discs, for transmitting an envelope the flap of which is to be opened from said first suction cylinder to said stop abutment, thence in a reverse direction by said third suction cylinder to said flap opener and thence to said delivery discs, and for transmitting an envelope the flap of which is to be folded against the front side from said first suction cylinder to said second suction cylinder, thence to said folding pocket and thence by said third suction cylinder to said delivery discs.

2. An apparatus according to claim 1, wherein said first suction cylinder comprises a rotary middle part having a row of suction apertures and two side parts concentrical to said middle part and located adjacent to said middle part on opposite sides thereof, said side parts rotating in a direction opposite to that of said middle part.

3. An apparatus according to claim 1, comprising slippreventing friction members carried by said third suction cylinder. 

1. A flap folding apparatus for an envelopemaking machine, said apparatus comprising a first suction cylinder receiving the made envelopes, a second suction cylinder, a third suction cylinder, said second and third suction cylinders being located adjacent said first suction cylinder and being adapted to receive envelopes from said first suction cylinder, an adjustable stop abutment adjacent said first suction cylinder, a flap opener adjacent said first and third suction cylinders, a folding pocket adjacent said second and third suction cylinders, delivery discs adjacent said third suction cylinder, and means actuating said suction cylinders for transmitting an envelope the flap of which remains closed consecutively by first, second and third suction cylinders to the delivery discs, for transmitting an envelope the flap of which is to be opened from said first suction cylinder to said stop abutment, thence in a reverse direction by said third suction cylinder to said flap opener and thence to said delivery discs, and for transmitting an envelope the flap of which is to be folded against the front side from said first suction cylinder to said second suction cylinder, thence to said folding pocket and thence by said third suction cylinder to said delivery discs.
 2. An apparatus according to claim 1, wherein said first suction cylinder comprises a rotary middle part having a row of suction apertures and two side parts concentrical to said middle part and located adjacent to said middle part on opposite sides thereof, said side parts rotating in a direction opposite to that of said middle part.
 3. An apparatus according to claim 1, comprising slip-preventing friction members carried by said third suction cylinder. 